The present invention relates to spatial compounding. Steered spatial compounding is used in clinical environments. One component frame of data is acquired by scanning along scan lines at one angle or pattern relative to a transducer. A second component frame of data is acquired by scanning along scan lines at a different angle or pattern. The transducer is held at substantially one position on the patient for acquiring the sequential component frames of data. Each of the frames of data represents an overlapping region of a patient. The frames of data are compounded together and displayed as an image.
Steered spatial compounding in ultrasound reduces speckle noise. Compounding component frames of data associated with different scan angles may reduce speckle and produce a more continuous border in specular targets, such as muscle layers. However, the improvement of signal-to-noise ratio may be limited by averaging signals from different steered angles with motion or uneven signal strength. In steered spatial compounding, the signal intensity for the same target location may be different among different views or steering angles. Simple averaging of those signals may reduce the signal-to-noise ratio. The problem is worse when motion occurs between acquisitions of the signals for the different views. Motion blur and lack of details due to averaging may be undesired.